For those who missed this when it was announced:

"Microsoft recommends that organizations who are using Automatic
Updates in their environments and wish to prevent users from
automatically receiving Internet Explorer 7 take one or more of the
following steps:"...


http://www.microsoft.com/technet/upd...ouncement.mspx

Internet Explorer 7 Blocker Toolkit: Frequently Asked Questions:

http://www.microsoft.com/technet/upd...ertoolfaq.mspx

Blocking should be in place by November 1st.